well i was 13 when i started (nearly 14) and now i have just turned 15 and will be starting pointe in a few months i have also moved up 3 grades and done 2 shows!
so of course you can im even starting tap and modern soon just find a dance studio and get going if you have any other question ill be happy to answer
You can join ballet at any age if that is what you are asking but it would help if you could be a little bit more specific go to your question and click Edit and Add Details to explain more.
You can definatly join! You would probably be in a lower class wit people maybe younger than you so you would have to really focus and pay attention to get with the kids your age!